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s` <br />Memo to Dan Mathews <br />1999 Powderhorn Subsidence Report <br />page 2 <br />apparent such as ridge lines. Finally, no manmade or specific critical natural <br />features were undermined during 1999. <br />As required by condition, five permanent survey monuments, placed in selected <br />locations above the projected workings, were resurveyed for comparison with <br />previous years monitoring observations. Within the required statistical accuracy <br />of the survey, none of these monuments demonstrated any subsidence. <br />The author concludes: "There is no evidence of subsidence related damage caused <br />by mining operation in the last year. No dangerous subsidence related features <br />were located during the surface investigation or survey of the subsidence <br />monuments. The operator was not notified that subsidence has affected any <br />structures, water supplies or environmentally sensitive areas." <br />This report, which roughly follows the format developed and implemented by Mr. <br />Larry Reschke, P.E., provides an adequate record of subsidence observations <br />conducted at the Roadside complex during 1999. I recommend it's acceptance. <br />cc: Larry Routten <br />Doc: M:\COAL\JAP\PDW99SUB.WPD <br />JP/1P <br />